The resonances of a collinear ABA molecule with a double Morse potential well are computed by means of complex scaling. For each symmetry, this system has about 40 resonances in 10 channels. The extraction of the resonance parameters from the raw data has been automatized, allowing the computation of all resonances for more than 40 values of the kinetic coupling parameter delta = m(A)/(m(A) + m(B)). Mean acid standard deviation of the width Gamma as function of delta show an interesting structure, which corresponds to the behavior of the classical unimolecular decay rates determined from trajectory calculations. Unexpectedly, we noticed that Fermi’s golden rule for Gamma breaks down already for values of delta near 0.1.